(a)

1. (1) The Arkansas Natural Resources Commission further defines the geographic boundaries of the designated nutrient surplus areas listed in 15 CAR § 6-201 by utilizing the National Datasets for Natural Resource Analysis.

2. (2) Hydrologic units have been classified based on data compiled by:

   1. (A) The United States Geological Survey;
   2. (B) The United States Natural Resources Conservation Service; and
   3. (C) Others.
3. (3) Each hydrologic unit is identified by a unique hydrologic unit code (HUC).
4. (4) Detailed maps and digital coverage of the boundaries are available at the commission office or district office.

5. (5) Hydrologic unit codes for the nutrient surplus areas are as follows:

   1. (A) Illinois River watershed, HUC 11110103;
   2. (B) Spavinaw Creek watershed, HUC 11070209;
   3. (C) Honey Creek watershed, HUC 11070206;
   4. (D) Little Sugar Creek watershed, HUC 11070208;
   5. (E) Upper Arkansas River watershed (which includes Lee Creek within Crawford and Washington counties and Massard Creek within Sebastian County), HUC 11110104;
   6. (F) Poteau River watershed, HUC 11110105;
   7. (G) Mountain Fork of the Little River watershed, HUC 11140108; and
   8. (H) Upper White River watershed above its confluence with the Buffalo River, HUC 11010001 and HUC 11010003 (excluding coverage under HUC 1101000308, 1101000309, 1101000310, and 110100031108).